/*-
 * Copyright (c) 2006 Bernd Walter.  All rights reserved.
 * Copyright (c) 2006 M. Warner Losh.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Portions of this software may have been developed with reference to
 * the SD Simplified Specification.  The following disclaimer may apply:
 *
 * The following conditions apply to the release of the simplified
 * specification ("Simplified Specification") by the SD Card Association and
 * the SD Group. The Simplified Specification is a subset of the complete SD
 * Specification which is owned by the SD Card Association and the SD
 * Group. This Simplified Specification is provided on a non-confidential
 * basis subject to the disclaimers below. Any implementation of the
 * Simplified Specification may require a license from the SD Card
 * Association, SD Group, SD-3C LLC or other third parties.
 *
 * Disclaimers:
 *
 * The information contained in the Simplified Specification is presented only
 * as a standard specification for SD Cards and SD Host/Ancillary products and
 * is provided "AS-IS" without any representations or warranties of any
 * kind. No responsibility is assumed by the SD Group, SD-3C LLC or the SD
 * Card Association for any damages, any infringements of patents or other
 * right of the SD Group, SD-3C LLC, the SD Card Association or any third
 * parties, which may result from its use. No license is granted by
 * implication, estoppel or otherwise under any patent or other rights of the
 * SD Group, SD-3C LLC, the SD Card Association or any third party. Nothing
 * herein shall be construed as an obligation by the SD Group, the SD-3C LLC
 * or the SD Card Association to disclose or distribute any technical
 * information, know-how or other confidential information to any third party.
 *
 * $FreeBSD: src/sys/dev/mmc/mmcsd.c,v 1.20 2009/02/17 19:17:25 mav Exp $
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/buf.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/disk.h>
#include <sys/device.h>
#include <sys/devicestat.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/spinlock.h>

#include <sys/buf2.h>

#include <bus/mmc/bridge.h>
#include <bus/mmc/mmcvar.h>
#include <bus/mmc/mmcreg.h>

#include "mmcbus_if.h"

struct mmcsd_softc {
        device_t dev;
        cdev_t dev_t;
        struct lock sc_lock;
        struct disk disk;
        struct devstat device_stats;
        struct thread *td;
        struct bio_queue_head bio_queue;
        daddr_t eblock, eend;   /* Range remaining after the last erase. */
        int running;
        int suspend;
};

/* bus entry points */
static int mmcsd_probe(device_t dev);
static int mmcsd_attach(device_t dev);
static int mmcsd_detach(device_t dev);

/* disk routines */
static d_open_t mmcsd_open;
static d_close_t mmcsd_close;
static d_strategy_t mmcsd_strategy;
static d_dump_t mmcsd_dump;

static void mmcsd_task(void *arg);

static const char *mmcsd_card_name(device_t dev);
static int mmcsd_bus_bit_width(device_t dev);

#define MMCSD_LOCK(_sc)         lockmgr(&(_sc)->sc_lock, LK_EXCLUSIVE)
#define MMCSD_UNLOCK(_sc)       lockmgr(&(_sc)->sc_lock, LK_RELEASE)
#define MMCSD_LOCK_INIT(_sc)    lockinit(&(_sc)->sc_lock, "mmcsd", 0, LK_CANRECURSE)
#define MMCSD_LOCK_DESTROY(_sc) lockuninit(&(_sc)->sc_lock);
#define MMCSD_ASSERT_LOCKED(_sc) KKASSERT(lockowned(&(_sc)->sc_lock));
#define MMCSD_ASSERT_UNLOCKED(_sc) KKASSERT(!lockowned(&(_sc)->sc_lock));

static struct dev_ops mmcsd_ops = {
        { "mmcsd", 0, D_DISK | D_MPSAFE },
        .d_open = mmcsd_open,
        .d_close = mmcsd_close,
        .d_strategy = mmcsd_strategy,
        .d_dump = mmcsd_dump,
};

static int
mmcsd_probe(device_t dev)
{

        device_quiet(dev);
        device_set_desc(dev, "MMC/SD Memory Card");
        return (0);
}

static int
mmcsd_attach(device_t dev)
{
        struct mmcsd_softc *sc;
        struct disk_info info;
        cdev_t dsk;
        intmax_t mb;
        char unit;
        int sector_size;

        sc = device_get_softc(dev);
        sc->dev = dev;
        MMCSD_LOCK_INIT(sc);

        sector_size = mmc_get_sector_size(dev);
        devstat_add_entry(&sc->device_stats, "mmcsd", device_get_unit(dev),
            sector_size, DEVSTAT_NO_ORDERED_TAGS,
            DEVSTAT_TYPE_DIRECT | DEVSTAT_TYPE_IF_OTHER,
            DEVSTAT_PRIORITY_DISK);

        bioq_init(&sc->bio_queue);

        sc->running = 1;
        sc->suspend = 0;
        sc->eblock = sc->eend = 0;
        kthread_create(mmcsd_task, sc, &sc->td, "mmc/sd card task");

        /*
         * Probe capacity
         */
        bzero(&info, sizeof(info));
        info.d_media_blksize = sector_size;
        info.d_media_blocks = mmc_get_media_size(dev);
        info.d_secpertrack = 1024;
        info.d_nheads = 1;
        info.d_secpercyl = info.d_secpertrack * info.d_nheads;
        info.d_ncylinders =  (u_int)(info.d_media_blocks / info.d_secpercyl);

        /*
         * Display in most natural units.  There's no cards < 1MB.
         * The SD standard goes to 2GiB, but the data format supports
         * up to 4GiB and some card makers push it up to this limit.
         * The SDHC standard only goes to 32GiB (the data format in
         * SDHC is good to 2TiB however, which isn't too ugly at
         * 2048GiBm, so we note it in passing here and don't add the
         * code to print TiB).
         *
         * 1MiB == 1 << 20
         */
        mb = (info.d_media_blksize * info.d_media_blocks) >> 20;
        unit = 'M';
        if (mb >= 10240) {              /* 1GiB = 1024 MiB */
                unit = 'G';
                mb /= 1024;
        }

        device_printf(dev, "%ju%cB <%s Memory Card>%s at %s %dMHz/%dbit\n",
            mb, unit, mmcsd_card_name(dev),
            mmc_get_read_only(dev) ? " (read-only)" : "",
            device_get_nameunit(device_get_parent(dev)),
            mmc_get_tran_speed(dev) / 1000000, mmcsd_bus_bit_width(dev));

        /*
         * SC is fully initialized, we can attach the drive now.  The
         * instant we do the kernel will start probing it.
         */
        dsk = disk_create(device_get_unit(dev), &sc->disk, &mmcsd_ops);
        dsk->si_drv1 = sc;
        sc->dev_t = dsk;

        /* Maximum defined SD card AU size. */
        dsk->si_iosize_max = 4*1024*1024;

        disk_setdiskinfo(&sc->disk, &info);

        return (0);
}

static int
mmcsd_detach(device_t dev)
{
        struct mmcsd_softc *sc = device_get_softc(dev);
        struct buf *q_bp;
        struct bio *q_bio;

        MMCSD_LOCK(sc);
        sc->suspend = 0;
        if (sc->running > 0) {
                /* kill thread */
                sc->running = 0;
                wakeup(sc);
                /* wait for thread to finish. */
                while (sc->running != -1)
                        lksleep(sc, &sc->sc_lock, 0, "detach", 0);
        }
        MMCSD_UNLOCK(sc);

        /*
         * Flush the request queue.
         *
         * XXX: Return all queued I/O with ENXIO. Is this correct?
         */
        while ((q_bio = bioq_takefirst(&sc->bio_queue)) != NULL) {
                q_bp = q_bio->bio_buf;
                q_bp->b_resid = q_bp->b_bcount;
                q_bp->b_error = ENXIO;
                q_bp->b_flags |= B_ERROR;
                biodone(q_bio);
        }

        /* kill disk */
        disk_destroy(&sc->disk);
        devstat_remove_entry(&sc->device_stats);

        MMCSD_LOCK_DESTROY(sc);

        return (0);
}

static int
mmcsd_suspend(device_t dev)
{
        struct mmcsd_softc *sc = device_get_softc(dev);

        MMCSD_LOCK(sc);
        sc->suspend = 1;
        if (sc->running > 0) {
                /* kill thread */
                sc->running = 0;
                wakeup(sc);
                /* wait for thread to finish. */
                while (sc->running != -1)
                        lksleep(sc, &sc->sc_lock, 0, "detach", 0);
        }
        MMCSD_UNLOCK(sc);
        return (0);
}

static int
mmcsd_resume(device_t dev)
{
        struct mmcsd_softc *sc = device_get_softc(dev);

        MMCSD_LOCK(sc);
        sc->suspend = 0;
        if (sc->running <= 0) {
                sc->running = 1;
                MMCSD_UNLOCK(sc);
                kthread_create(mmcsd_task, sc, &sc->td, "mmc/sd card task");
        } else
                MMCSD_UNLOCK(sc);
        return (0);
}

static int
mmcsd_open(struct dev_open_args *ap __unused)
{
        struct mmcsd_softc *sc;

        sc = (struct mmcsd_softc *)ap->a_head.a_dev->si_drv1;
        if ((ap->a_oflags & FWRITE) && mmc_get_read_only(sc->dev))
                return (EACCES);

        return (0);
}

static int
mmcsd_close(struct dev_close_args *ap __unused)
{
        return (0);
}

static int
mmcsd_strategy(struct dev_strategy_args *ap)
{
        struct mmcsd_softc *sc;
        struct bio *bio = ap->a_bio;
        struct buf *bp = bio->bio_buf;

        sc = (struct mmcsd_softc *)ap->a_head.a_dev->si_drv1;
        MMCSD_LOCK(sc);
        if (sc->running > 0 || sc->suspend > 0) {
                bioqdisksort(&sc->bio_queue, bio);
                MMCSD_UNLOCK(sc);
                wakeup(sc);
        } else {
                MMCSD_UNLOCK(sc);
                bp->b_error = ENXIO;
                bp->b_flags |= B_ERROR;
                bp->b_resid = bp->b_bcount;
                biodone(bio);
        }
        return (0);
}

static daddr_t
mmcsd_rw(struct mmcsd_softc *sc, struct bio *bio)
{
        daddr_t block, end;
        struct mmc_command cmd;
        struct mmc_command stop;
        struct mmc_request req;
        struct mmc_data data;
        device_t dev = sc->dev;
        int sz = sc->disk.d_info.d_media_blksize;
        struct buf *bp = bio->bio_buf;

        block = bio->bio_offset / sz;
        end = block + (bp->b_bcount / sz);
        while (block < end) {
                char *vaddr = bp->b_data +
                    (block - (bio->bio_offset / sz)) * sz;
                int numblocks = min(end - block, mmc_get_max_data(dev));
                memset(&req, 0, sizeof(req));
                memset(&cmd, 0, sizeof(cmd));
                memset(&stop, 0, sizeof(stop));
                req.cmd = &cmd;
                cmd.data = &data;
                if (bp->b_cmd == BUF_CMD_READ) {
                        if (numblocks > 1)
                                cmd.opcode = MMC_READ_MULTIPLE_BLOCK;
                        else
                                cmd.opcode = MMC_READ_SINGLE_BLOCK;
                } else {
                        if (numblocks > 1)
                                cmd.opcode = MMC_WRITE_MULTIPLE_BLOCK;
                        else
                                cmd.opcode = MMC_WRITE_BLOCK;
                }
                cmd.arg = block;
                if (!mmc_get_high_cap(dev))
                        cmd.arg <<= 9;
                cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
                data.data = vaddr;
                data.mrq = &req;
                if (bp->b_cmd == BUF_CMD_READ)
                        data.flags = MMC_DATA_READ;
                else
                        data.flags = MMC_DATA_WRITE;
                data.len = numblocks * sz;
                if (numblocks > 1) {
                        data.flags |= MMC_DATA_MULTI;
                        stop.opcode = MMC_STOP_TRANSMISSION;
                        stop.arg = 0;
                        stop.flags = MMC_RSP_R1B | MMC_CMD_AC;
                        req.stop = &stop;
                }
//              kprintf("Len %d  %lld-%lld flags %#x sz %d\n",
//                  (int)data.len, (long long)block, (long long)end, data.flags, sz);
                MMCBUS_WAIT_FOR_REQUEST(device_get_parent(dev), dev, &req);
                if (req.cmd->error != MMC_ERR_NONE)
                        break;
                block += numblocks;
        }
        return (block);
}

static daddr_t
mmcsd_delete(struct mmcsd_softc *sc, struct bio *bio)
{
        daddr_t block, end, start, stop;
        struct mmc_command cmd;
        struct mmc_request req;
        device_t dev = sc->dev;
        int sz = sc->disk.d_info.d_media_blksize;
        int erase_sector;
        struct buf *bp = bio->bio_buf;

        block = bio->bio_offset / sz;
        end = block + (bp->b_bcount / sz);
        /* Coalesce with part remaining from previous request. */
        if (block > sc->eblock && block <= sc->eend)
                block = sc->eblock;
        if (end >= sc->eblock && end < sc->eend)
                end = sc->eend;
        /* Safe round to the erase sector boundaries. */
        erase_sector = mmc_get_erase_sector(dev);
        start = block + erase_sector - 1;        /* Round up. */
        start -= start % erase_sector;
        stop = end;                             /* Round down. */
        stop -= end % erase_sector;
        /* We can't erase area smaller then sector, store it for later. */
        if (start >= stop) {
                sc->eblock = block;
                sc->eend = end;
                return (end);
        }

        /* Set erase start position. */
        memset(&req, 0, sizeof(req));
        memset(&cmd, 0, sizeof(cmd));
        req.cmd = &cmd;
        if (mmc_get_card_type(dev) == mode_sd)
                cmd.opcode = SD_ERASE_WR_BLK_START;
        else
                cmd.opcode = MMC_ERASE_GROUP_START;
        cmd.arg = start;
        if (!mmc_get_high_cap(dev))
                cmd.arg <<= 9;
        cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
        MMCBUS_WAIT_FOR_REQUEST(device_get_parent(dev), dev, &req);
        if (req.cmd->error != MMC_ERR_NONE) {
            kprintf("erase err1: %d\n", req.cmd->error);
            return (block);
        }
        /* Set erase stop position. */
        memset(&req, 0, sizeof(req));
        memset(&cmd, 0, sizeof(cmd));
        req.cmd = &cmd;
        if (mmc_get_card_type(dev) == mode_sd)
                cmd.opcode = SD_ERASE_WR_BLK_END;
        else
                cmd.opcode = MMC_ERASE_GROUP_END;
        cmd.arg = stop;
        if (!mmc_get_high_cap(dev))
                cmd.arg <<= 9;
        cmd.arg--;
        cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
        MMCBUS_WAIT_FOR_REQUEST(device_get_parent(dev), dev, &req);
        if (req.cmd->error != MMC_ERR_NONE) {
            kprintf("erase err2: %d\n", req.cmd->error);
            return (block);
        }
        /* Erase range. */
        memset(&req, 0, sizeof(req));
        memset(&cmd, 0, sizeof(cmd));
        req.cmd = &cmd;
        cmd.opcode = MMC_ERASE;
        cmd.arg = 0;
        cmd.flags = MMC_RSP_R1B | MMC_CMD_AC;
        MMCBUS_WAIT_FOR_REQUEST(device_get_parent(dev), dev, &req);
        if (req.cmd->error != MMC_ERR_NONE) {
            kprintf("erase err3 %d\n", req.cmd->error);
            return (block);
        }
        /* Store one of remaining parts for the next call. */
        if ((bio->bio_offset / sz) >= sc->eblock || block == start) {
                sc->eblock = stop;      /* Predict next forward. */
                sc->eend = end;
        } else {
                sc->eblock = block;     /* Predict next backward. */
                sc->eend = start;
        }
        return (end);
}

static int
mmcsd_dump(struct dev_dump_args *ap)
{
#if 0
        cdev_t cdev = ap->a_head.a_dev;
        struct mmcsd_softc *sc = (struct mmcsd_softc *)cdev->si_drv1;
        device_t dev = sc->dev;
        struct bio bp;
        daddr_t block, end;
        int length = ap->a_length;

        /* length zero is special and really means flush buffers to media */
        if (!length)
                return (0);

        bzero(&bp, sizeof(struct bio));
        bp.bio_driver_info = cdev;
        bp.bio_pblkno = offset / sc->disk->d_sectorsize;
        bp.bio_bcount = length;
        bp.bio_data = virtual;
        bp.bio_cmd = BIO_WRITE;
        end = bp.bio_pblkno + bp.bio_bcount / sc->disk.d_info.d_media_blksize;
        MMCBUS_ACQUIRE_BUS(device_get_parent(dev), dev);
        block = mmcsd_rw(sc, &bp);
        MMCBUS_RELEASE_BUS(device_get_parent(dev), dev);
        return ((end < block) ? EIO : 0);
#endif
        return EIO;
}

static void
mmcsd_task(void *arg)
{
        struct mmcsd_softc *sc = (struct mmcsd_softc*)arg;
        struct bio *bio;
        struct buf *bp;
        int sz;
        daddr_t block, end;
        device_t dev;

        dev = sc->dev;

        while (1) {
                MMCSD_LOCK(sc);
                do {
                        if (sc->running == 0)
                                goto out;
                        bio = bioq_takefirst(&sc->bio_queue);
                        if (bio == NULL)
                                lksleep(sc, &sc->sc_lock, 0, "jobqueue", 0);
                } while (bio == NULL);
                MMCSD_UNLOCK(sc);
                bp = bio->bio_buf;
                devstat_start_transaction(&sc->device_stats);
                MMCBUS_ACQUIRE_BUS(device_get_parent(dev), dev);
                sz = sc->disk.d_info.d_media_blksize;
                block = bio->bio_offset / sz;
                end = block + (bp->b_bcount / sz);
                if (bp->b_cmd == BUF_CMD_READ ||
                    bp->b_cmd == BUF_CMD_WRITE) {
                        /* Access to the remaining erase block obsoletes it. */
                        if (block < sc->eend && end > sc->eblock)
                                sc->eblock = sc->eend = 0;
                        block = mmcsd_rw(sc, bio);
                } else if (bp->b_cmd == BUF_CMD_FREEBLKS) {
                        block = mmcsd_delete(sc, bio);
                }
                MMCBUS_RELEASE_BUS(device_get_parent(dev), dev);
                if (block < end) {
                        bp->b_error = EIO;
                        bp->b_resid = (end - block) * sz;
                        bp->b_flags |= B_ERROR;
                } else {
                        bp->b_resid = 0;
                }
                devstat_end_transaction_buf(&sc->device_stats, bp);
                biodone(bio);
        }
out:
        /* tell parent we're done */
        sc->running = -1;
        MMCSD_UNLOCK(sc);
        wakeup(sc);
}

static const char *
mmcsd_card_name(device_t dev)
{
        if (mmc_get_card_type(dev) == mode_mmc)
                return ("MMC");
        if (mmc_get_high_cap(dev))
                return ("SDHC");
        return ("SD");
}

static int
mmcsd_bus_bit_width(device_t dev)
{
        if (mmc_get_bus_width(dev) == bus_width_1)
                return (1);
        if (mmc_get_bus_width(dev) == bus_width_4)
                return (4);
        return (8);
}

static device_method_t mmcsd_methods[] = {
        DEVMETHOD(device_probe, mmcsd_probe),
        DEVMETHOD(device_attach, mmcsd_attach),
        DEVMETHOD(device_detach, mmcsd_detach),
        DEVMETHOD(device_suspend, mmcsd_suspend),
        DEVMETHOD(device_resume, mmcsd_resume),
        DEVMETHOD_END
};

static driver_t mmcsd_driver = {
        "mmcsd",
        mmcsd_methods,
        sizeof(struct mmcsd_softc),
};
static devclass_t mmcsd_devclass;

DRIVER_MODULE(mmcsd, mmc, mmcsd_driver, mmcsd_devclass, NULL, NULL);